1. Field of the Invention
The present invention relates to a boot for the practice of any form of sport, but has a particularly advantageous application in the practice of so-called "aggressive" in-line roller skating.
Therefore, the boot according to the invention is especially adapted to be fixed on the upper plate of a chassis of an in-line roller skate, and has an external sole overlaid by a forwardly open upper to allow for passage of a user's foot.
To this end, it has two quarters demarcating an opening which are adapted to be connected to one another by a tightening lace.
Such a lace follows a path that is determined as a function of the position of return elements or guides, arranged on both sides of the quarters, which define a lacing zone, such that during a tractional action on the lace, the latter acts by bringing the quarters closer together to ensure the tightening of the foot.
2. Description of Background and Material Information
Generally speaking, the prior art teaches, as is the case in the documents U.S. Pat. No. 1,368,971 and CH 377 225, to carry out the lacing of the boot by means of return elements or guides constituted, for example, by eyelets provided on the edges of the boot quarters. The consequence is a rapid abrasive wear of the laces in the passing zone in the eyelets.
This is especially true for more violent sports which cause an intense friction of the top of the boot, and this is precisely the case of the so-called "aggressive" in-line roller skating which leads the user to perform gliding figures, through contact of the top of the skate along metallic rails or concrete walls, etc. It is readily understood that in this case, the laces are subjected to a very substantial abrasive effect as well as to a shearing effect.
One could think that the use of hooks, as taught by document DE 498 864, for example, could provide a solution to the problem of abrasion, for the lace would be protected by the upper portion of the hook.
While this may appear to be a solution to the problem addressed, it does however create another problem in that since the hooks are generally directed outwardly, and are therefore expressed, they in fact constitute potential hooking points with all kinds of external elements and with the boots with one another during acrobatic figures.
Therefore, this represents a real danger in this type of sport.
Consequently, it has proven indispensable to provide maximum protection for all the parts of the skate for the so-called "aggressive" in-line roller skating and, more particularly, for the upper portion of the boot upper in the lacing area.
The document GB 15,314 teaches the use of lacing hooks or equivalents which are covered by movable protective caps journalled on the fastening axes of the hooks of the boot. However, each hook is arranged in a planar configuration and is covered by the protective cap, such that passage of the lace is accessible only when the cap is rotationally displaced by the pressure applied by the lace on the cap. To actuate the opening of the cap, the lace must apply a force until overcoming the elastic resistance exerted by a leaf spring maintaining the hook in place beneath the cap. A major disadvantage is due to the fact that the lace engages into a passage of the hook that is perpendicular to the protective cap, which can cause substantial friction of the lace against the cap. Such a friction wears down the lace, especially when the lace is relatively thick, as is generally the case in sport boots. Moreover, the serial mounting of a plurality of this type of hooks can make tightening difficult due to the addition of this friction. The engagement of the lace in also uncertain due to the fact that the lace can slide along the cap without definitely opening it. In particular, such a disadvantage can appear after a while, when the rotating elements become corroded or dirty. Such a device, generally speaking, is also very complicated and expensive to make for a very questionable reliability.
Other documents, such as DE 145 156, DE 17 61 170, and EP 717 942, exist; but they provide inadequate protection for the lace, in view of the aggressive use to which it is intended in the present application.
Therefore, a system for passing the lace has been sought, to allow protection of the latter efficiently against abrasion, to facilitate the return of the lace without generating friction, and to avoid risking any hooking that would be caused by projections.